These blanks are definitely refillable. I find the best vapor when I tap the tip of the cartridge or twist it around the atomizer so the cotton-like material falls down to touch the atomizer.

A prior review said that they include plugs which I was disapointed to find mine did not come with, although that person does not speak on behalf of the company.
*Our blank cartridges now have plugs* VolcanoEcigs